Design specifications for the 25HP model, including the back axle, gearbox, and radiator.
| Identifier | ExFiles\Box 5a\1\ 01-page014 | |
| Date | 1st January 1931 | |
| F. {Mr Friese} DA. {Bernard Day - Chassis Design} } FROM R. {Sir Henry Royce} BY. {R.W. Bailey - Chief Engineer} HS. {Lord Ernest Hives - Chair} } (At Le Canadel(Henry Royce's French residence).) Y 5770 R2/Mil.1.31. Copy to SG. {Arthur F. Sidgreaves - MD} WOR. {Arthur Wormald - General Works Manager} re. 25HP. SPECIFICATION. I agree to all the points E. {Mr Elliott - Chief Engineer} mentions, but some may lead to delays, it being difficult to change our methods and get really first class designs and results quickly. We never have done but if we keep to ways well known to us we can get along as quickly as SG. {Arthur F. Sidgreaves - MD} and WOR. {Arthur Wormald - General Works Manager} hope and expect. I am delighted at the enterprise and vigour shown on this work by all. Exactly how we do it is of less importance than doing it quickly. Therefore I suggest we keep our back axle system the same as P. 2. This is already made and being run though at the moment I am not sure that it is perfect. Personally I like our P. 2. back axle better than the banjo type. It is smaller for a given wheel size and it builds up more accurately square, and in line. The materials and workmanship should not be more costly if proper comparisons are made. We must still have our full floating axle - i.e. wheels carried entirely by non-revolving axles. I entirely agree about the gearbox. It will need redesigning on the lines of P. 2. box. This is simpler than the present 25HP. box. It is to have no double top. single helical constant mesh 3rd. by dog clutch, and otherwise much like P.2. R.H. We must find a good and simple treatment for the L.H. certainly using the same wheels, but also as many of the other parts as a good design will allow. I hope to see a rough layout for both R.H. and L.H. before too much finishing time is put into it. Also a scheme for the separately cased radiator to facilitate chromium plating. R. {Sir Henry Royce} | ||
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).